
<!DOCTYPE HTML>
<html lang="" >
    <head>
        <meta charset="UTF-8">
        <meta content="text/html; charset=utf-8" http-equiv="Content-Type">
        <title>词法语法分析 · GitBook</title>
        <meta http-equiv="X-UA-Compatible" content="IE=edge" />
        <meta name="description" content="">
        <meta name="generator" content="GitBook 3.2.3">
        
        
        
    
    
    <link rel="stylesheet" href="../../gitbook/style.css">

    
            
                
                <link rel="stylesheet" href="../../gitbook/gitbook-plugin-chapter-fold/chapter-fold.css">
                
            
                
                <link rel="stylesheet" href="../../gitbook/gitbook-plugin-katex/katex.min.css">
                
            
                
                <link rel="stylesheet" href="../../gitbook/gitbook-plugin-alerts/style.css">
                
            
                
                <link rel="stylesheet" href="../../gitbook/gitbook-plugin-emphasize/plugin.css">
                
            
                
                <link rel="stylesheet" href="../../gitbook/gitbook-plugin-mermaid-gb3/mermaid/mermaid.css">
                
            
                
                <link rel="stylesheet" href="../../gitbook/gitbook-plugin-codeblock-label/block.css">
                
            
                
                <link rel="stylesheet" href="../../gitbook/gitbook-plugin-code/plugin.css">
                
            
                
                <link rel="stylesheet" href="../../gitbook/gitbook-plugin-search-pro/search.css">
                
            
                
                <link rel="stylesheet" href="../../gitbook/gitbook-plugin-click-reveal/click_reveal.css">
                
            
                
                <link rel="stylesheet" href="../../gitbook/gitbook-plugin-expandable-chapters-interactive/expandable-chapters.css">
                
            
                
                <link rel="stylesheet" href="../../gitbook/gitbook-plugin-highlight/website.css">
                
            
                
                <link rel="stylesheet" href="../../gitbook/gitbook-plugin-search/search.css">
                
            
                
                <link rel="stylesheet" href="../../gitbook/gitbook-plugin-fontsettings/website.css">
                
            
        

    

    
        
        <link rel="stylesheet" href="../../styles/website.css">
        
    
        
    
        
    
        
    
        
    
        
    


    

        
    
    
    <meta name="HandheldFriendly" content="true"/>
    <meta name="viewport" content="width=device-width, initial-scale=1, user-scalable=no">
    <meta name="apple-mobile-web-app-capable" content="yes">
    <meta name="apple-mobile-web-app-status-bar-style" content="black">
    <link rel="apple-touch-icon-precomposed" sizes="152x152" href="../../gitbook/images/apple-touch-icon-precomposed-152.png">
    <link rel="shortcut icon" href="../../gitbook/images/favicon.ico" type="image/x-icon">

    
    <link rel="next" href="part1-1-task.html" />
    
    
    <link rel="prev" href="part0-intro.html" />
    

    </head>
    <body>
        
<div class="book">
    <div class="book-summary">
        
            
<div id="book-search-input" role="search">
    <input type="text" placeholder="Type to search" />
</div>

            
                <nav role="navigation">
                


<ul class="summary">
    
    

    

    
        
        
    
        <li class="chapter " data-level="1.1" data-path="../../">
            
                <a href="../../">
            
                    
                    实验简介
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.2" data-path="../log.html">
            
                <a href="../log.html">
            
                    
                    更新日志
            
                </a>
            

            
        </li>
    

    
        
        <li class="header">零：前置准备</li>
        
        
    
        <li class="chapter " data-level="2.1" >
            
                <span>
            
                    
                    配环境、跑测试
            
                </span>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="2.1.1" data-path="../lab0/env.html">
            
                <a href="../lab0/env.html">
            
                    
                    环境配置
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="2.1.2" data-path="../lab0/testing.html">
            
                <a href="../lab0/testing.html">
            
                    
                    运行测试样例
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="2.1.3" data-path="../lab0/riscv.html">
            
                <a href="../lab0/riscv.html">
            
                    
                    RISC-V 的工具链使用
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    

    
        
        <li class="header">第一个编译器</li>
        
        
    
        <li class="chapter " data-level="3.1" >
            
                <span>
            
                    
                    step1：仅一个 return 的 main 函数
            
                </span>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="3.1.1" data-path="../lab1/part1.html">
            
                <a href="../lab1/part1.html">
            
                    
                    从零开始的 lexer、parser 以及汇编生成
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.1.2" data-path="../lab1/part2.html">
            
                <a href="../lab1/part2.html">
            
                    
                    词法语法分析工具
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.1.3" data-path="../lab1/part3.html">
            
                <a href="../lab1/part3.html">
            
                    
                    使用中间码
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.1.4" >
            
                <span>
            
                    
                    其他
            
                </span>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="3.1.4.1" data-path="../lab1/antlr.html">
            
                <a href="../lab1/antlr.html">
            
                    
                    ANTLR 使用
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.1.4.2" data-path="../lab1/visitor.html">
            
                <a href="../lab1/visitor.html">
            
                    
                    Visitor 模式
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.1.4.3" data-path="../lab1/ir.html">
            
                <a href="../lab1/ir.html">
            
                    
                    IR 简明介绍
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="3.1.5" data-path="../lab1/spec.html">
            
                <a href="../lab1/spec.html">
            
                    
                    规范
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    

    
        
        <li class="header">常量表达式</li>
        
        
    
        <li class="chapter " data-level="4.1" >
            
                <span>
            
                    
                    step2：一元操作
            
                </span>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="4.1.1" data-path="../lab2/intro.html">
            
                <a href="../lab2/intro.html">
            
                    
                    任务概述
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="4.1.2" data-path="../lab2/guide.html">
            
                <a href="../lab2/guide.html">
            
                    
                    实验指导
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="4.1.3" data-path="../lab2/spec.html">
            
                <a href="../lab2/spec.html">
            
                    
                    规范
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="4.2" >
            
                <span>
            
                    
                    step3：加减乘除模
            
                </span>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="4.2.1" data-path="../lab3/intro.html">
            
                <a href="../lab3/intro.html">
            
                    
                    任务概述
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="4.2.2" data-path="../lab3/guide.html">
            
                <a href="../lab3/guide.html">
            
                    
                    实验指导
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="4.2.3" data-path="../lab3/spec.html">
            
                <a href="../lab3/spec.html">
            
                    
                    规范
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="4.3" >
            
                <span>
            
                    
                    step4：比较和逻辑表达式
            
                </span>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="4.3.1" data-path="../lab4/intro.html">
            
                <a href="../lab4/intro.html">
            
                    
                    任务概述
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="4.3.2" data-path="../lab4/guide.html">
            
                <a href="../lab4/guide.html">
            
                    
                    实验指导
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="4.3.3" data-path="../lab4/spec.html">
            
                <a href="../lab4/spec.html">
            
                    
                    规范
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    

    
        
        <li class="header">变量和语句</li>
        
        
    
        <li class="chapter " data-level="5.1" >
            
                <span>
            
                    
                    step5：局部变量和赋值
            
                </span>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="5.1.1" data-path="../lab5/intro.html">
            
                <a href="../lab5/intro.html">
            
                    
                    任务概述
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="5.1.2" data-path="../lab5/guide.html">
            
                <a href="../lab5/guide.html">
            
                    
                    实验指导
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="5.1.3" >
            
                <span>
            
                    
                    其他
            
                </span>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="5.1.3.1" data-path="../lab5/stackframe.html">
            
                <a href="../lab5/stackframe.html">
            
                    
                    栈帧
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="5.1.4" data-path="../lab5/spec.html">
            
                <a href="../lab5/spec.html">
            
                    
                    规范
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="5.2" >
            
                <span>
            
                    
                    step6：if 语句和条件表达式
            
                </span>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="5.2.1" data-path="../lab6/part0-intro.md">
            
                <span>
            
                    
                    摘要
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="5.2.2" data-path="../lab6/part1-parse.md">
            
                <span>
            
                    
                    词法语法分析
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="5.2.3" data-path="../lab6/part1-1-task.md">
            
                <span>
            
                    
                    任务
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="5.2.4" data-path="../lab6/part4-codegen.md">
            
                <span>
            
                    
                    代码生成
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="5.2.5" data-path="../lab6/part4-1-task.md">
            
                <span>
            
                    
                    任务
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="5.2.6" data-path="../lab6/summary.md">
            
                <span>
            
                    
                    小结
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="5.2.7" data-path="../lab6/spec.html">
            
                <a href="../lab6/spec.html">
            
                    
                    规范
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    

    
        
        <li class="header">块语句和作用域和更多语句</li>
        
        
    
        <li class="chapter " data-level="6.1" >
            
                <span>
            
                    
                    step7：块语句
            
                </span>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="6.1.1" data-path="../lab7/part0-intro.html">
            
                <a href="../lab7/part0-intro.html">
            
                    
                    摘要
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="6.1.2" data-path="../lab7/part1-parse.html">
            
                <a href="../lab7/part1-parse.html">
            
                    
                    词法语法分析
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="6.1.3" data-path="../lab7/part1-1-task.html">
            
                <a href="../lab7/part1-1-task.html">
            
                    
                    任务
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="6.1.4" data-path="../lab7/part4-codegen.html">
            
                <a href="../lab7/part4-codegen.html">
            
                    
                    代码生成
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="6.1.5" data-path="../lab7/part4-1-task.html">
            
                <a href="../lab7/part4-1-task.html">
            
                    
                    任务
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="6.1.6" data-path="../lab7/summary.html">
            
                <a href="../lab7/summary.html">
            
                    
                    小结
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="6.1.7" data-path="../lab7/spec.html">
            
                <a href="../lab7/spec.html">
            
                    
                    规范
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="6.2" >
            
                <span>
            
                    
                    step8：循环语句
            
                </span>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="6.2.1" data-path="part0-intro.html">
            
                <a href="part0-intro.html">
            
                    
                    摘要
            
                </a>
            

            
        </li>
    
        <li class="chapter active" data-level="6.2.2" data-path="part1-parse.html">
            
                <a href="part1-parse.html">
            
                    
                    词法语法分析
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="6.2.3" data-path="part1-1-task.html">
            
                <a href="part1-1-task.html">
            
                    
                    任务
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="6.2.4" data-path="part4-codegen.html">
            
                <a href="part4-codegen.html">
            
                    
                    代码生成
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="6.2.5" data-path="part4-1-task.html">
            
                <a href="part4-1-task.html">
            
                    
                    任务
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="6.2.6" data-path="summary.html">
            
                <a href="summary.html">
            
                    
                    小结
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="6.2.7" data-path="spec.html">
            
                <a href="spec.html">
            
                    
                    规范
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    

    
        
        <li class="header">函数和全局变量</li>
        
        
    
        <li class="chapter " data-level="7.1" >
            
                <span>
            
                    
                    step9：函数
            
                </span>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="7.1.1" data-path="../lab9/part0-intro.html">
            
                <a href="../lab9/part0-intro.html">
            
                    
                    摘要
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.1.2" data-path="../lab9/part1-parser.html">
            
                <a href="../lab9/part1-parser.html">
            
                    
                    词法语法分析
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.1.3" data-path="../lab9/part1-1-task.html">
            
                <a href="../lab9/part1-1-task.html">
            
                    
                    任务
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.1.4" data-path="../lab9/part4-1-cconv.html">
            
                <a href="../lab9/part4-1-cconv.html">
            
                    
                    调用约定
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.1.5" data-path="../lab9/part4-2-codegen.html">
            
                <a href="../lab9/part4-2-codegen.html">
            
                    
                    代码生成
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.1.6" data-path="../lab9/part4-3-task.html">
            
                <a href="../lab9/part4-3-task.html">
            
                    
                    任务
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.1.7" data-path="../lab9/summary.html">
            
                <a href="../lab9/summary.html">
            
                    
                    小结
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.1.8" data-path="../lab9/spec.html">
            
                <a href="../lab9/spec.html">
            
                    
                    规范
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="7.2" >
            
                <span>
            
                    
                    step10：全局变量
            
                </span>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="7.2.1" data-path="../lab10/part0-intro.html">
            
                <a href="../lab10/part0-intro.html">
            
                    
                    摘要
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.2.2" data-path="../lab10/part1-parser.html">
            
                <a href="../lab10/part1-parser.html">
            
                    
                    词法语法分析
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.2.3" data-path="../lab10/part1-1-task.html">
            
                <a href="../lab10/part1-1-task.html">
            
                    
                    任务
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.2.4" data-path="../lab10/part4-codegen.html">
            
                <a href="../lab10/part4-codegen.html">
            
                    
                    代码生成
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.2.5" data-path="../lab10/part4-1-task.html">
            
                <a href="../lab10/part4-1-task.html">
            
                    
                    任务
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.2.6" data-path="../lab10/summary.html">
            
                <a href="../lab10/summary.html">
            
                    
                    小结
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.2.7" data-path="../lab10/spec.html">
            
                <a href="../lab10/spec.html">
            
                    
                    规范
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    

    
        
        <li class="header">指针和数组</li>
        
        
    
        <li class="chapter " data-level="8.1" >
            
                <span>
            
                    
                    step11：指针
            
                </span>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="8.1.1" data-path="../lab11/part0-intro.html">
            
                <a href="../lab11/part0-intro.html">
            
                    
                    摘要
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="8.1.2" data-path="../lab11/typeck.html">
            
                <a href="../lab11/typeck.html">
            
                    
                    类型检查
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="8.1.3" data-path="../lab11/part4-codegen.html">
            
                <a href="../lab11/part4-codegen.html">
            
                    
                    代码生成
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="8.1.4" data-path="../lab11/part4-1-task.html">
            
                <a href="../lab11/part4-1-task.html">
            
                    
                    任务
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="8.1.5" data-path="../lab11/summary.html">
            
                <a href="../lab11/summary.html">
            
                    
                    小结
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="8.1.6" data-path="../lab11/spec.html">
            
                <a href="../lab11/spec.html">
            
                    
                    规范
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="8.2" >
            
                <span>
            
                    
                    step12：数组
            
                </span>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="8.2.1" data-path="../lab12/part0-intro.html">
            
                <a href="../lab12/part0-intro.html">
            
                    
                    摘要
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="8.2.2" data-path="../lab12/part4-codegen.html">
            
                <a href="../lab12/part4-codegen.html">
            
                    
                    代码生成
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="8.2.3" data-path="../lab12/part4-1-task.html">
            
                <a href="../lab12/part4-1-task.html">
            
                    
                    任务
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="8.2.4" data-path="../lab12/summary.html">
            
                <a href="../lab12/summary.html">
            
                    
                    小结
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="8.2.5" data-path="../lab12/spec.html">
            
                <a href="../lab12/spec.html">
            
                    
                    规范
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    

    
        
        <li class="header">参考资料</li>
        
        
    
        <li class="chapter " data-level="9.1" data-path="../../REFERENCE.html">
            
                <a href="../../REFERENCE.html">
            
                    
                    参考资料
            
                </a>
            

            
        </li>
    

    

    <li class="divider"></li>

    <li>
        <a href="https://www.gitbook.com" target="blank" class="gitbook-link">
            Published with GitBook
        </a>
    </li>
</ul>


                </nav>
            
        
    </div>

    <div class="book-body">
        
            <div class="body-inner">
                
                    

<div class="book-header" role="navigation">
    

    <!-- Title -->
    <h1>
        <i class="fa fa-circle-o-notch fa-spin"></i>
        <a href="../.." >词法语法分析</a>
    </h1>
</div>




                    <div class="page-wrapper" tabindex="-1" role="main">
                        <div class="page-inner">
                            
<div id="book-search-results">
    <div class="search-noresults">
    
<div id="book-search-results">
    <div class="search-noresults">
    
                                <section class="normal markdown-section">
                                
                                <h1 id="&#x8BCD;&#x6CD5;&#x8BED;&#x6CD5;&#x89E3;&#x6790;">&#x8BCD;&#x6CD5;&#x8BED;&#x6CD5;&#x89E3;&#x6790;</h1>
<h3 id="while-&#x8BED;&#x53E5;"><code>while</code> &#x8BED;&#x53E5;</h3>
<p>&#x4E3A; <code>&lt;statement&gt;</code> &#x65B0;&#x589E;&#x5982;&#x4E0B;&#x4EA7;&#x751F;&#x5F0F;&#xFF1A;</p>
<pre><code>&lt;statement&gt; ::= ...  // &#x5DF2;&#x6709;&#x7684;&#x5176;&#x4ED6;&#x4EA7;&#x751F;&#x5F0F;
              | &quot;while&quot; &quot;(&quot; &lt;exp&gt; &quot;)&quot; &lt;statement&gt;
</code></pre><p>&#x5176;&#x4E2D; <code>&quot;while&quot;</code> &#x662F;&#x65B0;&#x7684;&#x6807;&#x8BB0;&#xFF0C;&#x5E94;&#x5728;&#x8BCD;&#x6CD5;&#x5206;&#x6790;&#x5668;&#x4E2D;&#x5B9E;&#x73B0;&#x3002;</p>
<p>&#x65B0;&#x589E;&#x5982;&#x4E0B; AST &#x7ED3;&#x70B9;&#xFF1A;</p>
<pre><code>statement = ...  // &#x5DF2;&#x6709;&#x7684;&#x5176;&#x4ED6;&#x7ED3;&#x70B9;
          | While(expression, statement)
</code></pre><p>&#x5176;&#x4E2D; <code>expression</code> &#x548C; <code>statement</code> &#x5206;&#x522B;&#x4E3A;&#x5FAA;&#x73AF;&#x6761;&#x4EF6;&#x548C;&#x5FAA;&#x73AF;&#x4F53;&#x3002;</p>
<h3 id="do-while-&#x8BED;&#x53E5;"><code>do while</code> &#x8BED;&#x53E5;</h3>
<p>&#x4E3A; <code>&lt;statement&gt;</code> &#x65B0;&#x589E;&#x5982;&#x4E0B;&#x4EA7;&#x751F;&#x5F0F;&#xFF1A;</p>
<pre><code>&lt;statement&gt; ::= ...  // &#x5DF2;&#x6709;&#x7684;&#x5176;&#x4ED6;&#x4EA7;&#x751F;&#x5F0F;
              | &quot;do&quot; &lt;statement&gt; &quot;while&quot; &quot;(&quot; &lt;exp&gt; &quot;)&quot; &quot;;&quot;
</code></pre><p>&#x5176;&#x4E2D; <code>&quot;do&quot;</code> &#x662F;&#x65B0;&#x7684;&#x6807;&#x8BB0;&#xFF0C;&#x5E94;&#x5728;&#x8BCD;&#x6CD5;&#x5206;&#x6790;&#x5668;&#x4E2D;&#x5B9E;&#x73B0;&#x3002;</p>
<p>&#x65B0;&#x589E;&#x5982;&#x4E0B; AST &#x7ED3;&#x70B9;&#xFF1A;</p>
<pre><code>statement = ...  // &#x5DF2;&#x6709;&#x7684;&#x5176;&#x4ED6;&#x7ED3;&#x70B9;
          | Do(statement, expression)
</code></pre><p>&#x5176;&#x4E2D; <code>expression</code> &#x548C; <code>statement</code> &#x5206;&#x522B;&#x4E3A;&#x5FAA;&#x73AF;&#x6761;&#x4EF6;&#x548C;&#x5FAA;&#x73AF;&#x4F53;&#x3002;</p>
<h3 id="for-&#x8BED;&#x53E5;"><code>for</code> &#x8BED;&#x53E5;</h3>
<p>&#x76F8;&#x5BF9;&#x4E8E; <code>while</code> &#x8BED;&#x53E5;&#x548C; <code>do while</code> &#x8BED;&#x53E5;&#xFF0C;<code>for</code> &#x8BED;&#x53E5;&#x8F83;&#x4E3A;&#x590D;&#x6742;&#x3002;<code>for</code> &#x8BED;&#x53E5;&#x53EF;&#x80FD;&#x6709;&#x5982;&#x4E0B;&#x53D8;&#x79CD;&#xFF1A;</p>
<ul>
<li><code>for</code> &#x7684;&#x7B2C;&#x4E00;&#x4E2A;&#x5206;&#x53F7;&#x524D;&#xFF0C;&#x53EF;&#x80FD;&#x662F;&#x8BED;&#x53E5;&#xFF0C;&#x4E5F;&#x53EF;&#x80FD;&#x662F;&#x5FAA;&#x73AF;&#x53D8;&#x91CF;&#x7684;&#x5B9A;&#x4E49;&#xFF1B;</li>
<li><code>for</code> &#x7684;&#x521D;&#x59CB;&#x5316;&#x8BED;&#x53E5;&#x3001;&#x5FAA;&#x73AF;&#x6761;&#x4EF6;&#x548C;&#x81EA;&#x589E;&#x8BED;&#x53E5;&#x5747;&#x53EF;&#x4EE5;&#x4E3A;&#x7A7A;&#x3002;</li>
</ul>
<p>&#x4E3A;&#x6B64;&#xFF0C;&#x6211;&#x4EEC;&#x6309;&#x5982;&#x4E0B;&#x65B9;&#x5F0F;&#x8BBE;&#x8BA1;&#x6587;&#x6CD5;&#xFF1A;</p>
<pre><code>&lt;statement&gt; ::= ...  // &#x5DF2;&#x6709;&#x7684;&#x5176;&#x4ED6;&#x4EA7;&#x751F;&#x5F0F;
              | &quot;for&quot; &quot;(&quot; &lt;exp-option-semicolon&gt; &lt;exp-option-semicolon&gt; &lt;exp-option-close-paren&gt; &lt;statement&gt;
              | &quot;for&quot; &quot;(&quot; &lt;declaration&gt; &lt;exp-option-semicolon&gt; &lt;exp-option-close-paren&gt; &lt;statement&gt;
&lt;exp-option-semicolon&gt; ::= &lt;exp&gt; &quot;;&quot; | &quot;;&quot;
&lt;exp-option-close-paren&gt; ::= &lt;exp&gt; &quot;)&quot; | &quot;)&quot;
</code></pre><p>&#x5176;&#x4E2D; <code>&quot;for&quot;</code> &#x662F;&#x65B0;&#x7684;&#x6807;&#x8BB0;&#xFF0C;&#x5E94;&#x5728;&#x8BCD;&#x6CD5;&#x5206;&#x6790;&#x5668;&#x4E2D;&#x5B9E;&#x73B0;&#x3002;</p>
<p>&#x5F53;&#x7136;&#xFF0C;&#x8FD9;&#x53EA;&#x662F;&#x80FD;&#x89E3;&#x6790; <code>for</code> &#x8BED;&#x53E5;&#x7684;&#x5176;&#x4E2D;&#x4E00;&#x79CD;&#x6587;&#x6CD5;&#x3002;&#x4F60;&#x4E5F;&#x53EF;&#x4EE5;&#x8BBE;&#x8BA1;&#x4E00;&#x4E2A;&#x6807;&#x8BB0;&#x8868;&#x793A;&#x201C;&#x8868;&#x8FBE;&#x5F0F;&#x6216;&#x7A7A;&#x201D;&#xFF0C;&#x4EE5;&#x66FF;&#x6362; <code>&lt;exp-option-semicolon&gt;</code> &#x548C; <code>&lt;exp-option-close-paren&gt;</code>&#xFF0C;&#x6216;&#x662F;&#x6309;&#x4F60;&#x559C;&#x6B22;&#x7684;&#x5176;&#x4ED6;&#x65B9;&#x5F0F;&#x8BBE;&#x8BA1;&#x3002;</p>
<p>&#x89E3;&#x6790;&#x5668;&#x5E94;&#x751F;&#x6210;&#x5982;&#x4E0B;  AST &#x7ED3;&#x70B9;&#xFF1A;</p>
<pre><code>statement = ...  // &#x5DF2;&#x6709;&#x7684;&#x5176;&#x4ED6;&#x7ED3;&#x70B9;
          | For(exp option, exp option, exp option, statement)
          | ForDecl(declaration, exp option, exp option, statement)
</code></pre><p>&#x5176;&#x4E2D; <code>For</code> &#x548C; <code>ForDecl</code> &#x5206;&#x522B;&#x8868;&#x793A;&#x5728; <code>for</code> &#x8BED;&#x53E5;&#x4E2D;&#x4F7F;&#x7528;&#x521D;&#x59CB;&#x5316;&#x8BED;&#x53E5;&#x548C;&#x5B9A;&#x4E49;&#x5FAA;&#x73AF;&#x53D8;&#x91CF;&#x7684;&#x4E24;&#x79CD;&#x60C5;&#x51B5;&#x3002;AST &#x7ED3;&#x70B9;&#x7684;&#x5404;&#x4E2A;&#x53C2;&#x6570;&#x5206;&#x522B;&#x8868;&#x793A;&#x521D;&#x59CB;&#x5316;&#x8BED;&#x53E5;/&#x5FAA;&#x73AF;&#x53D8;&#x91CF;&#x5B9A;&#x4E49;&#x3001;&#x5FAA;&#x73AF;&#x6761;&#x4EF6;&#x3001;&#x81EA;&#x589E;&#x8BED;&#x53E5;&#x548C;&#x5FAA;&#x73AF;&#x4F53;&#x3002;&#x5982;&#x679C;&#x4F60;&#x5728;&#x7B2C;6&#x6B65;&#x9009;&#x62E9;&#x5C06; <code>Declaration</code> &#x4F5C;&#x4E3A;&#x4E00;&#x79CD; <code>statment</code>&#xFF0C;&#x90A3;&#x4E48;&#x53EA;&#x9700;&#x6DFB;&#x52A0; <code>For</code> &#x7ED3;&#x70B9;&#x5373;&#x53EF;&#xFF0C;&#x800C;&#x4E0D;&#x5FC5;&#x6DFB;&#x52A0; <code>ForDecl</code> &#x7ED3;&#x70B9;&#x3002;&#x6309;&#x8FD9;&#x79CD;&#x65B9;&#x5F0F;&#xFF0C;&#x4F60;&#x53EF;&#x80FD;&#x9700;&#x8981;&#x5728;&#x540E;&#x7EED;&#x6B65;&#x9AA4;&#x4E2D;&#x533A;&#x5206;&#x8FD9;&#x4E24;&#x79CD; <code>for</code> &#x8BED;&#x53E5;&#x3002;</p>
<p>&#x5E26; <code>option</code> &#x6807;&#x8BB0;&#x7684;&#x8868;&#x793A;&#x8BE5;&#x9879;&#x662F;&#x53EF;&#x9009;&#x7684;&#x3002;&#x4F60;&#x4E5F;&#x53EF;&#x4EE5;&#x9009;&#x62E9;&#x4E0D;&#x5728; AST &#x7ED3;&#x70B9;&#x4E2D;&#x8BBE;&#x8BA1;&#x53EF;&#x9009;&#x53C2;&#x6570;&#xFF0C;&#x800C;&#x662F;&#x6784;&#x9020;&#x4E00;&#x4E2A;&#x5E38;&#x91CF; <code>1</code> &#x7ED3;&#x70B9;&#x4EE3;&#x66FF;&#x7A7A;&#x7684;&#x5FAA;&#x73AF;&#x6761;&#x4EF6;&#x3001;&#x6784;&#x9020;&#x4E00;&#x4E2A;&#x7A7A;&#x8BED;&#x53E5;&#x5757;&#x7ED3;&#x70B9;&#x4EE3;&#x66FF;&#x7A7A;&#x7684;&#x521D;&#x59CB;&#x5316;&#x6216;&#x81EA;&#x589E;&#x8BED;&#x53E5;&#x3002;</p>
<h3 id="&#x7A7A;&#x8BED;&#x53E5;">&#x7A7A;&#x8BED;&#x53E5;</h3>
<p>&#x5728;&#x672C;&#x6B65;&#x9AA4;&#x4E2D;&#xFF0C;&#x6211;&#x4EEC;&#x8FD8;&#x8981;&#x5F15;&#x5165;&#x7A7A;&#x8BED;&#x53E5;&#x3002;&#x4F60;&#x53EF;&#x4EE5;&#x5229;&#x7528;&#x4E0A;&#x8FF0; <code>for</code> &#x8BED;&#x53E5;&#x4EA7;&#x751F;&#x5F0F;&#x4E2D;&#x7684; <code>&lt;exp-option-semicolon&gt;</code>&#xFF0C;&#x4F8B;&#x5982;&#xFF1A;</p>
<pre><code>&lt;statement&gt; ::= ...  // &#x5DF2;&#x6709;&#x7684;&#x5176;&#x4ED6;&#x4EA7;&#x751F;&#x5F0F;
              | &lt;exp-option-semicolon&gt; // null statement
</code></pre><p>&#x4E5F;&#x53EF;&#x4EE5;&#x8BBE;&#x8BA1;&#x5355;&#x72EC;&#x7684;&#x7A7A;&#x8BED;&#x53E5;&#x4EA7;&#x751F;&#x5F0F;&#x3002;</p>
<p>&#x5BF9;&#x4E8E; AST&#xFF0C;&#x4F60;&#x65E2;&#x53EF;&#x4EE5;&#x4F7F;&#x7528;&#x7A7A;&#x7684;&#x8BED;&#x53E5;&#x5757;&#x7ED3;&#x70B9;&#x8868;&#x793A;&#x7A7A;&#x8BED;&#x53E5;&#xFF0C;&#x4E5F;&#x53EF;&#x4EE5;&#x52A0;&#x5165;&#x4E13;&#x95E8;&#x8868;&#x793A;&#x7A7A;&#x8BED;&#x53E5;&#x7684;&#x7ED3;&#x70B9;&#xFF0C;&#x8FD8;&#x53EF;&#x4EE5;&#x5E72;&#x8106;&#x4E0D;&#x7528;&#x4EFB;&#x4F55;&#x7ED3;&#x70B9;&#x8868;&#x793A;&#x7A7A;&#x8BED;&#x53E5;&#x3002;</p>
<h3 id="break-&#x548C;-continue-&#x8BED;&#x53E5;"><code>break</code> &#x548C; <code>continue</code> &#x8BED;&#x53E5;</h3>
<p>&#x4E3A; <code>&lt;statement&gt;</code> &#x65B0;&#x589E;&#x5982;&#x4E0B;&#x4EA7;&#x751F;&#x5F0F;&#xFF1A;</p>
<pre><code>&lt;statement&gt; ::= ...  // &#x5DF2;&#x6709;&#x7684;&#x5176;&#x4ED6;&#x4EA7;&#x751F;&#x5F0F;
              | &quot;break&quot; &quot;;&quot;
              | &quot;continue&quot; &quot;;&quot;
</code></pre><p>&#x5176;&#x4E2D; <code>&quot;break&quot;</code> &#x548C; <code>&quot;continue&quot;</code> &#x5747;&#x662F;&#x65B0;&#x7684;&#x6807;&#x8BB0;&#xFF0C;&#x5E94;&#x5728;&#x8BCD;&#x6CD5;&#x5206;&#x6790;&#x5668;&#x4E2D;&#x5B9E;&#x73B0;&#x3002;</p>
<p>&#x65B0;&#x589E;&#x5982;&#x4E0B; AST &#x7ED3;&#x70B9;&#xFF1A;</p>
<pre><code>statement = ...  // &#x5DF2;&#x6709;&#x7684;&#x5176;&#x4ED6;&#x7ED3;&#x70B9;
          | Break
          | Continue
</code></pre><p>&#x503C;&#x5F97;&#x6CE8;&#x610F;&#x7684;&#x662F;&#xFF0C;&#x5982;&#x679C;&#x7A0B;&#x5E8F;&#x4E2D;&#x5B58;&#x5728;&#x4F4D;&#x4E8E;&#x5FAA;&#x73AF;&#x4F53;&#x5916;&#x90E8;&#x7684; <code>break</code> &#x6216; <code>continue</code>&#xFF0C;&#x4E0A;&#x8FF0;&#x6587;&#x6CD5;&#x5E76;&#x4E0D;&#x4F1A;&#x62A5;&#x9519;&#x3002;&#x4F60;&#x9700;&#x8981;&#x5728;&#x540E;&#x7EED;&#x6B65;&#x9AA4;&#x4E2D;&#x8FDB;&#x884C;&#x9A8C;&#x8BC1;&#xFF0C;&#x4E5F;&#x53EF;&#x4EE5;&#x6539;&#x8FDB;&#x6587;&#x6CD5;&#xFF0C;&#x5728;&#x8BED;&#x6CD5;&#x89E3;&#x6790;&#x9636;&#x6BB5;&#x5C31;&#x8BC6;&#x522B;&#x6B64;&#x7C7B;&#x9519;&#x8BEF;&#x3002;</p>

                                
                                </section>
                            
    </div>
    <div class="search-results">
        <div class="has-results">
            
            <h1 class="search-results-title"><span class='search-results-count'></span> results matching "<span class='search-query'></span>"</h1>
            <ul class="search-results-list"></ul>
            
        </div>
        <div class="no-results">
            
            <h1 class="search-results-title">No results matching "<span class='search-query'></span>"</h1>
            
        </div>
    </div>
</div>

    </div>
    <div class="search-results">
        <div class="has-results">
            
            <h1 class="search-results-title"><span class='search-results-count'></span> results matching "<span class='search-query'></span>"</h1>
            <ul class="search-results-list"></ul>
            
        </div>
        <div class="no-results">
            
            <h1 class="search-results-title">No results matching "<span class='search-query'></span>"</h1>
            
        </div>
    </div>
</div>

                        </div>
                    </div>
                
            </div>

            
                
                <a href="part0-intro.html" class="navigation navigation-prev " aria-label="Previous page: 摘要">
                    <i class="fa fa-angle-left"></i>
                </a>
                
                
                <a href="part1-1-task.html" class="navigation navigation-next " aria-label="Next page: 任务">
                    <i class="fa fa-angle-right"></i>
                </a>
                
            
        
    </div>

    <script>
        var gitbook = gitbook || [];
        gitbook.push(function() {
            gitbook.page.hasChanged({"page":{"title":"词法语法分析","level":"6.2.2","depth":2,"next":{"title":"任务","level":"6.2.3","depth":2,"path":"docs/lab8/part1-1-task.md","ref":"docs/lab8/part1-1-task.md","articles":[]},"previous":{"title":"摘要","level":"6.2.1","depth":2,"path":"docs/lab8/part0-intro.md","ref":"docs/lab8/part0-intro.md","articles":[]},"dir":"ltr"},"config":{"gitbook":"*","theme":"default","variables":{},"plugins":["hide-element","chapter-fold","katex","alerts","emphasize","mermaid-gb3","codeblock-label","code","search-pro","click-reveal","expandable-chapters-interactive","localized-footer"],"pluginsConfig":{"chapter-fold":{},"emphasize":{},"codeblock-label":{},"search-pro":{},"search":{},"localized-footer":{"filename":"gitalk.html","hline":"true"},"lunr":{"maxIndexSize":1000000,"ignoreSpecialCharacters":false},"code":{"copyButtons":true},"hide-element":{},"katex":{},"fontsettings":{"theme":"white","family":"sans","size":1},"click-reveal":{},"highlight":{},"mermaid-gb3":{},"expandable-chapters-interactive":{},"alerts":{},"sharing":{"facebook":true,"twitter":true,"google":false,"weibo":false,"instapaper":false,"vk":false,"all":["facebook","google","twitter","weibo","instapaper"]},"theme-default":{"styles":{"website":"styles/website.css","pdf":"styles/pdf.css","epub":"styles/epub.css","mobi":"styles/mobi.css","ebook":"styles/ebook.css","print":"styles/print.css"},"showLevel":false}},"structure":{"langs":"LANGS.md","readme":"README.md","glossary":"GLOSSARY.md","summary":"SUMMARY.md"},"pdf":{"pageNumbers":true,"fontSize":12,"fontFamily":"Arial","paperSize":"a4","chapterMark":"pagebreak","pageBreaksBefore":"/","margin":{"right":62,"left":62,"top":56,"bottom":56}},"styles":{"website":"styles/website.css","pdf":"styles/pdf.css","epub":"styles/epub.css","mobi":"styles/mobi.css","ebook":"styles/ebook.css","print":"styles/print.css"}},"file":{"path":"docs/lab8/part1-parse.md","mtime":"2020-09-02T07:27:37.427Z","type":"markdown"},"gitbook":{"version":"3.2.3","time":"2020-09-05T16:09:01.964Z"},"basePath":"../..","book":{"language":""}});
        });
    </script>
</div>

        
    
    <script src="../../gitbook/gitbook.js"></script>
    <script src="../../gitbook/theme.js"></script>
    
        
        <script src="../../gitbook/gitbook-plugin-hide-element/plugin.js"></script>
        
    
        
        <script src="../../gitbook/gitbook-plugin-chapter-fold/chapter-fold.js"></script>
        
    
        
        <script src="../../gitbook/gitbook-plugin-alerts/plugin.js"></script>
        
    
        
        <script src="../../gitbook/gitbook-plugin-mermaid-gb3/book/plugin.js"></script>
        
    
        
        <script src="../../gitbook/gitbook-plugin-code/plugin.js"></script>
        
    
        
        <script src="../../gitbook/gitbook-plugin-search-pro/jquery.mark.min.js"></script>
        
    
        
        <script src="../../gitbook/gitbook-plugin-search-pro/search.js"></script>
        
    
        
        <script src="../../gitbook/gitbook-plugin-click-reveal/click_reveal.js"></script>
        
    
        
        <script src="../../gitbook/gitbook-plugin-expandable-chapters-interactive/expandable-chapters.js"></script>
        
    
        
        <script src="../../gitbook/gitbook-plugin-search/search-engine.js"></script>
        
    
        
        <script src="../../gitbook/gitbook-plugin-search/search.js"></script>
        
    
        
        <script src="../../gitbook/gitbook-plugin-lunr/lunr.min.js"></script>
        
    
        
        <script src="../../gitbook/gitbook-plugin-lunr/search-lunr.js"></script>
        
    
        
        <script src="../../gitbook/gitbook-plugin-sharing/buttons.js"></script>
        
    
        
        <script src="../../gitbook/gitbook-plugin-fontsettings/fontsettings.js"></script>
        
    

    <script src="../../gitbook/gitbook-plugin-mermaid-gb3/mermaid/mermaid.min.js"></script>

    </body>
</html>

